How to execute a 180° bend with a bending radius that is smaller than half of the sheet thickness?

[Jonas]

Hey there,
I'm working on Alibre Design Expert 2018. In the screenshot attached, you can see what I'm trying to achieve.

I tried two ways:
1. Direct 180° bending with a bending radius of 0,75mm. -> Error
2. Making two 90° bends with 'bend only' activated, radius 0,75mm -> Error, with the first bend already.

I figured out, that this is more of a deforming of the sheet metal than a bend, because the bending radius is very small, I'm aware of this. Can I nevertheless do this with Alibre Design somehow?

Jonas

 

[simonb65]

Doesn't the bend radius need to be at the centre line of the sheet, i.e. 1.75mm rad? (Not at my PC right now, so can't check!)

 

[Jonas]

Doesn't the bend radius need to be at the centre line of the sheet, i.e. 1.75mm rad? (Not at my PC right now, so can't check!)

Hi Simon,
thanks for your question. The smallest radius i can bend without errrors is half of the sheet thickness. Don't know exactly what you mean.

 

[idslk]

The smallest radius i can bend without errrors is half of the sheet thickness.

sheet thickness in your sample = 2mm -> Alibre bend radius = 1 mm


to get your wished result, you have to tweak your parameters...




Regards
Stefan

 

[Jonas]

Hi Stefan,
thank you for your answer. But in my case, I need to have a distance of 1.5mm between the bended sheets. So I need to reduce the radius to 0.75mm. But this results in an Error. Is there a way to tweek my settings to get this result?

 

[Jonas]

sheet thickness in your sample = 2mm -> Alibre bend radius = 1 mm
View attachment 33698

to get your wished result, you have to tweak your parameters...
View attachment 33699

View attachment 33700

Regards
Stefan

Got it! I had to change the 'Mimimum Bendradius', too.

Thanks, Stefan for the quick help.
Have a good weekend

 

[DavidJ]

You have to reduce the Minimum Bend Radius value - the 'AD_Thickness/2' is just a default and may usually be sensible, but you can re-set that.

Looks like you found that as I was typing.

 

[Jonas]

Yes DavidJ. Thanks you for your answer nontheless!